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National Park Service Cave Ecology Inventory And Monitoring Framework, Gretchen M. Baker, Steven J. Taylor, Shawn Thomas, Rick Olson, Kathy Lavoie, Marie Denn, Steven Thomas, Hazel Barton, Kurt Helf, Rene Ohms, Joel Despain, Jim Kennedy, David Larson 2014 National Park Service

National Park Service Cave Ecology Inventory And Monitoring Framework, Gretchen M. Baker, Steven J. Taylor, Shawn Thomas, Rick Olson, Kathy Lavoie, Marie Denn, Steven Thomas, Hazel Barton, Kurt Helf, Rene Ohms, Joel Despain, Jim Kennedy, David Larson

Hazel Barton

A team developed the Cave Ecology Inventory and Monitoring Framework for National Park Service (NPS) units. It contains information for NPS cave managers across the United States to determine how to inventory and monitor cave ecology. Due to the wide geographical scope of NPS caves and their many different types, the document does not prescribe exact protocols. Instead, it provides guidance for what types of inventory and monitoring are possible, a framework for deciding how to prioritize inventory and monitoring activities, and references to specific protocols that are already in place at NPS cave parks. Keywords: cave ecology, cave microbiology, …


Identification And Characterization Of Phytoplankton In Barnegat Bay, New Jersey, Nicole L. Elia 2014 Seton Hall University

Identification And Characterization Of Phytoplankton In Barnegat Bay, New Jersey, Nicole L. Elia

Seton Hall University Dissertations and Theses (ETDs)

Barnegat Bay is a marine estuary that encompasses 670-square miles of the eastern coast of New Jersey. The bay serves as a home to thousands of species of plants, animals, and microorganisms. During the summer months, the population of the bay increases from 576,000 to over 1.5 million residents. In 2011, the Barnegat Bay Partnership reported that environmental conditions of the bay are declining due to increased pollutants from nutrient fertilizers and runoff. Increased nitrogen levels have led to eutrophication and proliferation of phytoplankton algal blooms. Harmful algal blooms (HABs) cause a decrease in dissolved oxygen levels in the water …


The Role Of Nitrogen And Phosphorus In The Growth, Toxicity, And Distribution Of The Toxic Cyanobacteria, Microcystis Aeruginosa, James Parrish 2014 University of San Francisco

The Role Of Nitrogen And Phosphorus In The Growth, Toxicity, And Distribution Of The Toxic Cyanobacteria, Microcystis Aeruginosa, James Parrish

Master's Projects and Capstones

Microcystis aeruginosa is among the most common harmful algal-blooming species in the world. Potent microcystins released by M. aeruginosa have been linked to liver failure and death in aquatic mammals, like the endangered California sea otter, and provide a serious public health risk to humans. Once characterized as a freshwater problem, M. aeruginosa is expanding on a global scale, making persistent returns in freshwater, brackish, and coastal marine ecosystems. Though commonly observed dominating aquatic ecosystems in low N:P atomic ratios less than 44:1, the reliability of N:P ratios as a tool for managing and predicting M. aeruginosa blooms is explored …


Microbe-Mineral Relationships And Biogenic Mineral Transformations In Actively Venting Deep-Sea Hydrothermal Sulfide Chimneys, TZIHSUAN J. LIN 2014 University of Massachusetts - Amherst

Microbe-Mineral Relationships And Biogenic Mineral Transformations In Actively Venting Deep-Sea Hydrothermal Sulfide Chimneys, Tzihsuan J. Lin

TZIHSUAN J LIN

This dissertation uses a combination of microbiology, mineralogy, and geochemistry to understand dissimilatory iron reduction in hyperthermophilic archaea and the role and potential impact of these and other vent microorganisms within active deep-sea hydrothermal vent chimneys. The central objective of the dissertation is to determine if mineral composition and chimney type are among the primary determinants of microbial community composition and hyperthermophilic, dissimilatory iron reducer growth, in addition to other environmental factors such as nutrient availability, temperature, pH, and chlorinity. This is done using samples and organisms collected from the Endeavour Segment of the Juan de Fuca Ridge in the …


Fruiting Bodies Of The Social Amoeba Dictyostelium Discoideum Increase Spore Transport By Drosophila, jeff smith, David C. Queller, Joan E. Strassmann 2014 Washington University in St Louis

Fruiting Bodies Of The Social Amoeba Dictyostelium Discoideum Increase Spore Transport By Drosophila, Jeff Smith, David C. Queller, Joan E. Strassmann

Biology Faculty Publications & Presentations

Background: Many microbial phenotypes are the product of cooperative interactions among cells, but their putative fitness benefits are often not well understood. In the cellular slime mold Dictyostelium discoideum , unicellular amoebae aggregate when starved and form multicellular fruiting bodies in which stress-resistant spores are held aloft by dead stalk cells. Fruiting bodies are thought to be adaptations for dispersing spores to new feeding sites, but this has not been directly tested. Here we experimentally test whether fruiting bodies increase the rate at which spores are acquired by passing invertebrates.
Results: Drosophila melanogaster accumulate spores on their surfaces more quickly …


Plant-Microbial Interactions Change Along A Prairie Restoration Chronosequence, Anna Herzberger 2014 Eastern Illinois University

Plant-Microbial Interactions Change Along A Prairie Restoration Chronosequence, Anna Herzberger

Undergraduate Honors Theses

Soil microbial communities are critical in determining the performance and density of species in plant communities. However, their role in regulating the success of restorations is much less clear. This study assessed the ability of soil microbial communities to regulate the growth and performance of two potentially dominant grasses and two common forbs in prairie restorations. Specifically, I examined the effects of soil microbial communities along a restoration chronosequence from agricultural fields to remnant prairies using experimentally inoculated soils. The two grass species, Andropogon gerardii and Sorghastrum nutans, produced larger biomass with the agricultural inoculates and experienced a decline …


Investigating Antibiotic Resistance Levels Of Salmonella Internalized In Lettuce Leaves, Jason B. Thomas 2014 University of Nebraska-Lincoln

Investigating Antibiotic Resistance Levels Of Salmonella Internalized In Lettuce Leaves, Jason B. Thomas

McNair Scholars Research Journal

Contamination of food crops by the human pathogen Salmonella is a food safety threat worldwide. Though using treated wastewater for irrigation is a sustainable practice, it may introduce trace levels of Salmonella that may contaminate food crops. Salmonella could develop resistance to antibiotics present in wastewater. The overall goal of the project is to increase the understanding of the public health risk associated with the use of treated wastewater to irrigate food crops. The objective of this particular study is to determine the antibiotic resistance level of Salmonella internalized in lettuce leaves. In this experiment, thirty-six plants of the lettuce …


Biosorption Of Heavy Metals Onto The Surface Of Bacteriophage T4, Zheng Huan Tan 2014 University of Nebraska-Lincoln

Biosorption Of Heavy Metals Onto The Surface Of Bacteriophage T4, Zheng Huan Tan

School of Biological Sciences: Dissertations, Theses, and Student Research

Biosorption of heavy metals by bacterial and eukaryotic cell surfaces and the subsequent transport in aqueous environments is well recognized. However, very little is known about the roles viruses play in biosorption. Viruses outnumber prokaryotes and eukaryotes in environmental systems. These organisms represent abundant nanoparticulate organic colloids with reactive surfaces. Here we conducted a series of experiments to assess the biosorption potential of Escherichia coli bacteriophage T4. Adsorption of a heavy metal, Zn2+, to the surface of phage T4 was tested in a series of purified phage/metal solutions (0 µM – 1000 µM at 23°C). The Langmuir isotherm …


Quantitative Depth Profile Of Prochlorococcus In The Pacific Ocean, Benjamin Carter Calfee 2014 University of Tennessee - Knoxville

Quantitative Depth Profile Of Prochlorococcus In The Pacific Ocean, Benjamin Carter Calfee

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

Prochlorococcus is a genus of extremely abundant marine cyanobacterium. This microbe is responsible for the majority of the primary production within marine environments and is thought to be the single most abundant photosynthetic organism. In addition to accounting for such a large portion of the world’s photosynthetic activity, Prochlorococcus functions with a genome much smaller than most other primary producers. Thus due to its general abundance and overall importance in oceanic ecosystems, an experiment was prompted to derive the spatial and numerical separation of the members of this genus across the Pacific Ocean through the use of quantitative polymerase chain …


Comparison Of Bacterial Communities Associated Spider Species Occupying Different Physical Environments, Jack Kang 2014 University of Tennessee - Knoxville

Comparison Of Bacterial Communities Associated Spider Species Occupying Different Physical Environments, Jack Kang

EURēCA: Exhibition of Undergraduate Research and Creative Achievement

No abstract provided.


Colonization Of Intestinal Pathogen Changes The Gut Microbiota, Kaitlyn Shondelmyer 2014 Liberty University

Colonization Of Intestinal Pathogen Changes The Gut Microbiota, Kaitlyn Shondelmyer

Senior Honors Theses

Enterohemorrhagic Escherechia coli is a serious human pathogen causing bloody diarrhea and hemolytic uremic syndrome. It is difficult to study in animal models, but pathogenesis may be modeled in mice with the similar murine pathogen, Citrobacter rodentium. C. rodentium does not cause disease in streptomycin-treated mice, suggesting that it is competition with other facultative anaerobes that triggers pathogenesis. Streptomycin-treated mice were co-colonized with C. rodentium and a commensal E. coli strain. The intestinal microbiota of each group was observed over a 15-day period using quantitative PCR. Colon weights were also measured over the same period. Results indicate that the …


Bioremediation Of Crude Oil Spills Impacts Microbial Communities And The Magnetic Susceptibility Of Sediments, Carol L. Beaver, Anja Williams, Estella Atekwana, Gamal Abdel Aal, Farag Mewafy, Lee Slater, Silvia Rossbach 2014 Western Michigan University

Bioremediation Of Crude Oil Spills Impacts Microbial Communities And The Magnetic Susceptibility Of Sediments, Carol L. Beaver, Anja Williams, Estella Atekwana, Gamal Abdel Aal, Farag Mewafy, Lee Slater, Silvia Rossbach

Research and Creative Activities Poster Day

A worldwide increase in the production, shipment, and storage of crude oil has led to an increase in oil spills, and efforts to physically remove this oil from the environment are often insufficient. As a result, hydrocarbon contamination that is not eliminated by suction, excavation, or by dispersants remains in the water and sediments to be degraded by microbes. Initially, the bioremediation of oil occurs aerobically, but as oxygen is depleted, microbes must switch to alternate electron acceptors. Gradients of terminal electron acceptors form over time, which in conjunction with the toxic properties of oil, have an effect on the …


Exploration Of Freshwater Cyanobacteria, Mariya Campbell 2014 Georgia State University

Exploration Of Freshwater Cyanobacteria, Mariya Campbell

Georgia State Undergraduate Research Conference

No abstract provided.


Environmental Influences On Bacterio-Phytoplanktonic Coupling And Bacterial Growth Efficiency In A Sub-Tropical Estuary, Rachel Kotkowski 2014 FIU

Environmental Influences On Bacterio-Phytoplanktonic Coupling And Bacterial Growth Efficiency In A Sub-Tropical Estuary, Rachel Kotkowski

FIU Electronic Theses and Dissertations

Bacterio-phytoplanktonic coupling and bacterial growth efficiency (BGE) measurements were used to analyze microbial trophic dynamics and the influence of environmental factors in Florida Bay, Florida. Phytoplankton gross primary productivity (GPP) was measured using 24-hour in situ oxygen incubations; bacterial productivity (BP) was measured using 3H- thymidine incorporation. Weak bacterio-phytoplanktonic coupling was observed over the sampling period. BP was more influenced by local total nitrogen concentrations while GPP was more evenly distributed. BGE rates were low but consistent with marine and estuarine ecosystems worldwide. Results suggest that bacterioplankton growth in Florida Bay is relatively uncoupled from phytoplankton production, which may …


Characterization Of Rhizobial Diversity And Relationship Of Rhizobial Partner And Legume Performance In Four South Florida Pine Rockland Soils, Vanessa Sánchez 2014 Florida International University

Characterization Of Rhizobial Diversity And Relationship Of Rhizobial Partner And Legume Performance In Four South Florida Pine Rockland Soils, Vanessa Sánchez

FIU Electronic Theses and Dissertations

Pine rocklands are endangered ecosystems unique to south Florida, the Bahamas and Cuba. As a result of their karstic calcium carbonate­rich soil, these systems are limited in phosphorus and nitrogen, making symbiotic associations critical to plant growth. Four leguminous species (Cajanus cajan, Chamaecrista fasciculata, Tephrosia angustissima, and Abrus precatorious) were used to determine the relationship between rhizobial partners and plant performance, and the symbiosis related gene nifH was amplified to characterize the diversity of rhizobial symbionts. Plants were grown in soils from four different south Florida pine rocklands, and a salinity treatment was added to determine …


The Roles Of Microcystin And Sulfide In Physiology And Tactic Responses Of Pathogenic And Non-Pathogenic Mat-Forming Cyanobacteria, Abigael C. Brownell 2014 Florida International University

The Roles Of Microcystin And Sulfide In Physiology And Tactic Responses Of Pathogenic And Non-Pathogenic Mat-Forming Cyanobacteria, Abigael C. Brownell

FIU Electronic Theses and Dissertations

Planktothricoides raciborskii and Roseofilum reptotaenium are physiologically similar, yet ecologically distinct organisms found in a hot spring outflow and coral black band disease (BBD), respectively. The aim of this study was to elucidate the relationship between R. reptotaenium and sulfide in BBD, to compare microcystin (MC) production in response to environmental factors, and to determine chemotactic responses to MC and sulfide by the two organisms. Results showed that the pathogenicity of R. reptotaenium in BBD is dependent on sulfate-reducing bacteria as secondary pathogens. Roseofilum reptotaenium produced significantly more MC than P. raciborskii, as measured using ELISA. Roseofilum reptotaenium …


Deletion Mutant Library For Investigation Of Functional Outputs Of Cyclic Diguanylate Metabolism In Pseudomonas Aeruginosa Pa14, Dae-Gon Ha, Megan E. Richman, George A. O'Toole 2014 Dartmouth College

Deletion Mutant Library For Investigation Of Functional Outputs Of Cyclic Diguanylate Metabolism In Pseudomonas Aeruginosa Pa14, Dae-Gon Ha, Megan E. Richman, George A. O'Toole

Dartmouth Scholarship

We constructed a library of in-frame deletion mutants targeting each gene in Pseudomonas aeruginosa PA14 predicted to participate in cyclic di-GMP (c-di-GMP) metabolism (biosynthesis or degradation) to provide a toolkit to assist investigators studying c-di-GMP-mediated regulation by this microbe. We present phenotypic assessments of each mutant, including biofilm formation, exopolysaccharide (EPS) production, swimming motility, swarming motility, and twitch motility, as a means to initially characterize these mutants and to demonstrate the potential utility of this library.


Structure And Function Of Zooplankton-Associated Bacterial Communities In A Temperate Estuary Change More With Time Than With Zooplankton Species, Samatha L. Bickel, Kam W. Tang, Hans-Peter Grossart 2014 Virginia Institute of Marine Science

Structure And Function Of Zooplankton-Associated Bacterial Communities In A Temperate Estuary Change More With Time Than With Zooplankton Species, Samatha L. Bickel, Kam W. Tang, Hans-Peter Grossart

VIMS Articles

Zooplankton support distinct bacterial communities in high concentrations relative to the surrounding water, but little is known about how the compositions and functionalities of these bacterial communities change through time in relation to environmental conditions. We conducted a year-long field study of bacterial communities associated with common zooplankton groups as well as free-living bacterial communities in the York River, a tributary of Chesapeake Bay. Bacterial community genetic fingerprints and their carbon substrate usage were examined by denaturing gradient gel electrophoresis (DGGE) of amplified 16S rDNA and by Biolog EcoPlates, respectively. Zooplankton-associated communities were genetically distinct from free-living bacterial communities but …


Comparafac: A Library And Tools For Rapid And Quantitative Comparison Of Dissolved Organic Matter Components Resolved By Parallel Factor Analysis., Thomas B. Parr, Tsutomu Ohno, Kevin Simon 2014 University of Maine - Orono

Comparafac: A Library And Tools For Rapid And Quantitative Comparison Of Dissolved Organic Matter Components Resolved By Parallel Factor Analysis., Thomas B. Parr, Tsutomu Ohno, Kevin Simon

Publications

Parallel Factor Analysis (PARAFAC) is a well-established method for characterizing dissolved organic matter (DOM). While methods for sample processing and PARAFAC analysis are well defined and robust, subsequent classification of DOM fluorescence components and comparisons of components among studies remain highly qualitative. Because these comparisons often guide the interpretation of subsequent data, it is important that quantitatively accurate comparisons be made. We developed a statistical tool, comPARAFAC, using a modified Tucker’s Congruence Coefficient (mTCC), an established method of factor comparison, to provide a quantitative basis for comparing models. To develop and test this tool we used mTCC to compare factors …


Transcriptome Analysis Of Listeria Monocytogenes Exposed To Biocide Stress Reveals A Multi-System Response Involving Cell Wall Synthesis, Sugar Uptake, And Motility, Aidan Casey, Edward M. Fox, Stephan Schmitz-Esser, Aidan Coffey, Olivia McAuliffe, Kieran Jordan 2014 Teagasc Food Research Centre, Fermoy, Ireland

Transcriptome Analysis Of Listeria Monocytogenes Exposed To Biocide Stress Reveals A Multi-System Response Involving Cell Wall Synthesis, Sugar Uptake, And Motility, Aidan Casey, Edward M. Fox, Stephan Schmitz-Esser, Aidan Coffey, Olivia Mcauliffe, Kieran Jordan

Department of Biological Sciences Publications

Listeria monocytogenes is a virulent food-borne pathogen most often associated with the consumption of “ready-to-eat” foods. The organism is a common contaminant of food processing plants where it may persist for extended periods of time. A commonly used approach for the control of Listeria monocytogenes in the processing environment is the application of biocides such as quaternary ammonium compounds. In this study, the transcriptomic response of a persistent strain of L. monocytogenes (strain 6179) on exposure to a sub-lethal concentration of the quaternary ammonium compound benzethonium chloride (BZT) was assessed. Using RNA-Seq, gene expression levels were quantified by sequencing …


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